Search Results (365)

Isolation of neurons and glia from the enteric nervous system (ENS) enables ex vivo studies, including the analysis of genomic and transcriptomic profiles. While we previously reported a fluorescence-activated cell sorting (FACS)-based isolation protocol for human ENS cells, no equivalent exists for mice. As directly applying the human protocol to mouse tissue resulted in low recovery of live ENS cells, we optimized tissue dissociation using mouse colons. A 30 min Liberase-based digestion showed optimal recovery of viable ENS cells, with CD56 and CD24 emerging as the most reliable markers to select and subdivide these cells. ENS’ identity was further validated by FACS, using neuronal (TUBB3) and glial (SOX10) markers and reverse transcriptase quantitative PCR on sorted fractions. Overall, the mouse ENS expression profile significantly overlapped with the human one, showing that current dissociation protocols yield a mixed population of enteric neurons and glia. Nonetheless, using the imaging flow cytometer BD S8 FACS Discover and ELAVL4 as a neuronal soma-associated marker, we observed enrichment of neurons in a CD56/CD24^TIP population. In conclusion, we present here a protocol for high-purity FACS-based isolation of viable mouse ENS cells, suitable for downstream applications. Full article

The study of the ground tip corona discharge is an important part of the lightning strike mechanism and lightning warning research. Because the characteristics of the corona charge distribution are difficult to observe directly, simulation research is indispensable. However, most of the previous models have been unipolar models, which cannot reflect the characteristics of the tip corona discharge under electric field reversal during real thunderstorms. Therefore, the development of three-dimensional positive and negative corona discharge models is of great significance. In this study, a three-dimensional corona discharge numerical model considering the polarity reversal process of the electric field was developed with or without a wind field and simulated the tip corona discharge characteristics under this reversal. The reliability of the model was verified by comparing the observed results. Compared with the unipolar corona discharge model, this model could effectively evaluate the impact of the first half-cycle corona discharge on the second half-cycle opposite-polarity corona discharge and invert the spatial separation distribution characteristics of different polar corona charges released in both cycles under the influence of wind and the spatial electric field distribution characteristics generated by the corresponding corona charges. Comparing unipolar corona discharges under the same wave pattern and amplitude of the background electric field, it was assumed that the unipolar corona discharge occurred in the half cycle after the polarity reversal of an electric field, and there was also an opposite-polarity corona discharge process before it. Due to the influence of the first half cycle, the background electric field required for a corona discharge was smaller, and the corona current was generated earlier, but the end time was equivalent. At the same time, due to the neutralization effect of positive and negative corona charges, the peak value of the total corona charge in the second half cycle was significantly smaller than that of the unipolar model. At different building heights, the peak difference in the corona current and the peak difference in the corona charge between the two models increased linearly with an increase in height. It could be seen that this model had better simulation results and wider application value. Full article

Causal discovery involves searching intractably large spaces. Decomposing the search space into classes of observationally equivalent causal models is a well-studied avenue to making discovery tractable. This paper studies the topological structure underlying causal equivalence to develop a categorical formulation of Chickering’s transformational characterization of Bayesian networks. A homotopic generalization of the Meek–Chickering theorem on the connectivity structure within causal equivalence classes and a topological representation of Greedy Equivalence Search (GES) that moves from one equivalence class of models to the next are described. Specifically, this work defines causal models as propable symmetric monoidal categories (cPROPs), which define a functor category ${\mathcal{C}}^P$ from a coalgebraic PROP P to a symmetric monoidal category $\mathcal{C}$. Such functor categories were first studied by Fox, who showed that they define the right adjoint of the inclusion of Cartesian categories in the larger category of all symmetric monoidal categories. cPROPs are an algebraic theory in the sense of Lawvere. cPROPs are related to previous categorical causal models, such as Markov categories and affine CDU categories, which can be viewed as defined by cPROP maps specifying the semantics of comonoidal structures corresponding to the “copy-delete” mechanisms. This work characterizes Pearl’s structural causal models (SCMs) in terms of Cartesian cPROPs, where the morphisms that define the endogenous variables are purely deterministic. A higher algebraic K-theory of causality is developed by studying the classifying spaces of observationally equivalent causal cPROP models by constructing their simplicial realization through the nerve functor. It is shown that Meek–Chickering causal DAG equivalence generalizes to induce a homotopic equivalence across observationally equivalent cPROP functors. A homotopic generalization of the Meek–Chickering theorem is presented, where covered edge reversals connecting equivalent DAGs induce natural transformations between homotopically equivalent cPROP functors and correspond to an equivalence structure on the corresponding string diagrams. The Grothendieck group completion of cPROP causal models is defined using the Grayson–Quillen construction and relate the classifying space of cPROP causal equivalence classes to classifying spaces of an induced groupoid. A real-world domain modeling genetic mutations in cancer is used to illustrate the framework in this paper. Full article

The prefabricated concrete channel, constructed by integrating factory-based prefabrication with on-site assembly, offers enhanced quality, reduced construction time, and minimized environmental impact. To promote its application in water conservancy projects, an innovative concrete joint combining semi-grouting sleeves and shear-resistant steel plates was proposed. Its seismic performance was assessed through a 1:3 scale low-cycle reversed loading test, focusing on failure mode, hysteretic behavior, skeleton curves, stiffness degradation, ductility, and energy dissipation. Results show that the joint primarily exhibits bending–shear failure, with cracks initiating at the sidewall–base slab interface. Also, the sidewall and base slab are interconnected through semi-grouting sleeves, while the concrete bonding is achieved via grouting and surface chiseling at the joint interface. The results indicated that the innovative concrete joint connection exhibits satisfied seismic performance. The shear-resistant steel plate significantly improves shear strength and enhances water sealing. Compared with cast-in-place specimens, the prefabricated joint shows a 16.04% lower equivalent viscous damping coefficient during failure due to reinforcement slippage, while achieving 16.34% greater cumulative energy dissipation and 52.00% higher ductility. These findings provide theoretical and experimental support for the broader adoption of prefabricated channels in water conservancy engineering. Full article

Recent work has demonstrated a correspondence that bridges quantum information processing and high-energy physics: discrete quantum cellular automata (QCA) can, in the continuum limit, reproduce quantum field theories (QFTs). This QCA/QFT correspondence raises fundamental questions about how matter/energy, information, and the nature of spacetime are related. Here, we show that free QED is equivalent to the continuous-space-and-time limit of Fermi and Bose QCA theories on the cubic lattice derived from quantum random walks satisfying simple symmetry and unitarity conditions. In doing so, we define the Fermi and Bose theories in a unified manner using the usual fermion internal space and a boson internal space that is six-dimensional. We show that the reduction to a two-dimensional boson internal space (two helicity states arising from spin-1 plus the photon transversality condition) comes from restricting the QCA theory to positive energies. We briefly examine common symmetries of QCAs and how time-reversal symmetry demands the existence of negative-energy solutions. These solutions produce a tension in coupling the Fermi and Bose theories, in which the strong locality of QCAs seems to require a non-zero amplitude to produce negative-energy states, leading to an unphysical cascade of negative-energy particles. However, we show in a 1D model that, by extending interactions over a larger (but finite) range, it is possible to exponentially suppress the production of negative-energy particles to the point where they can be neglected. Full article

The rapid development of the new energy vehicle industry has resulted in a significant number of waste electric vehicle batteries (WEVBs) reaching the end of their useful life. The recycling of these batteries holds both economic and environmental value. As policy is a critical factor influencing the recycling of waste electric vehicle batteries, its role in the network warrants deeper investigation. Based on this, this study integrates both subsidy and penalty policy into the design of the waste electric vehicle battery reverse logistics network (RLN), aiming to examine the effects of single policy and policy combinations, thereby filling the research gap in the existing literature that predominantly focuses on single-policy perspectives. Considering multiple battery types, different recycling technologies, and uncertain recycling quantities and qualities, this study develops a fuzzy mixed-integer programming model to optimize cost and carbon emission. The fuzzy model is transformed into a deterministic equivalent form using expected intervals, expected values, and fuzzy chance-constrained programming. By normalizing and weighting the upper and lower bounds of the multi-objective functions, the model is transformed into a single-objective optimization problem. The effectiveness of the proposed model and solution method was validated through an empirical study on the construction of a waste electric vehicle battery reverse logistics network in Zhengzhou City. The experimental results demonstrate that combined policy outperforms single policy in balancing economic benefits and environmental protection. The results provide decision-making support for policymakers and industry stakeholders in optimizing reverse logistics networks for waste electric vehicle batteries. Full article

The bruising of fruits occurs at various stages, including picking, transportation, and sale. For fruits with large kernels that occupy a significant portion of their overall volume, considering the impact of the kernel is crucial in elucidating the mechanisms of bruising and controlling bruise formation. This study employs reverse engineering to develop a composite finite element model of loquat peel, flesh, and kernels. Bruise formation during collisions is analyzed from the perspectives of contact force, equivalent stress, energy, bruise volume, and bruise susceptibility, aiming to reveal the significant role of the fruit core in the bruise formation process. In this paper, we propose the use of 3D printing technology to accurately quantify bruise measurement for fruits with large kernels. The results showed that the maximum contact force, equivalent stress, and internal energy between loquat and steel/wood were essentially consistent, but all exceeded those observed when using rubber. Due to the blocking of stress transmission by the kernel, the susceptibility of loquats to bruising increases with height before decreasing. This study elucidates the mechanism of bruise formation in fruits with large kernels and provides methods and ideas for the research and precise measurement of complex fruit bruising characteristics. Full article

Research has advocated for the use of incorrect worked examples targeting specific conceptual barriers to enhance learning. From the perspective of cognitive load theory, we examined the relationship between instructional efficiency (correct and incorrect worked examples [CICWEs] vs. worked examples [WEs] vs. problem-solving [PS]), levels of expertise (low vs. high), and belief in achievement best (realistic vs. optimal) in learning linear equations across two experiments (N = 43 vs. N = 68). In the CICWE group, students compared an incorrect step in the incorrect worked example with the parallel correct step in the correct worked example and justified why the step was wrong. The WE group completed multiple worked example–equation pairs, while the PS group solved equivalent linear equations independently. As hypothesized, the WE group outperformed the PS group for low prior knowledge students, while the reverse occurred for high prior knowledge students, demonstrating the expertise reversal effect. In contrast, the CICWE group did not outperform either the PS or WE group. A student’s indication of optimal best, reflecting what is known as the ‘realistic–optimal achievement bests dichotomy’, aligns with his or her belief in their ability to perform tasks of varying complexity (simple task vs. complex task). Regarding the belief in achieving optimal best as an outcome of instructional manipulation, for low prior knowledge students, there were no significant differences across groups on either the realistic best or optimal best subscales. However, for high prior knowledge students, the groups differed significantly on the optimal best subscale, but not on the realistic best subscale. Importantly, the mental effort invested during learning was unrelated to students’ belief in achieving their optimal best. Full article

The rapid proliferation of wireless devices and the escalating demand for ultra-reliable, high-capacity communication networks have propelled massive multiple-input multiple-output systems as a cornerstone technology for next-generation wireless standards. Massive multiple-input multiple-output systems deploy hundreds of antennas at both the transmitter and the receiver, leading to high computational complexity in many antenna selection algorithms. Existing approaches often achieve reduced complexity at the expense of partial performance compromise. To address this challenge, this paper proposes an Improved Branch-and-Bound Antenna Selection algorithm that reduces complexity while maintaining the required performance. The algorithm iteratively eliminates the antenna contributing least to channel capacity from the candidate set. Through the mechanism of reverse-stacking nodes, the conventional stack-based search process is modified. Most critically, by employing dynamic stack management and effective pruning conditions, substantial pruning operations can be implemented during subsequent search procedures, significantly accelerating the identification of the optimal antenna subset. Simulation results demonstrate that the improved algorithm reduces computational complexity from an order of 10³ to 10² while maintaining equivalent channel capacity. Furthermore, through a single execution, the algorithm can obtain optimal antenna subsets with varying sizes within specified ranges, effectively overcoming the limitation of the traditional Branch-and-Bound algorithm that requires repeated executions for different subset dimensions. Full article

Multisource and multimodal data fusion plays a pivotal role in large-scale artificial intelligence applications involving big data. However, the choice of fusion strategies for different scenarios is often based on experimental comparisons, which leads to increased computational costs during model training and suboptimal performance during testing. In this paper, we present a theoretical analysis of early fusion, late fusion, and gradual fusion methods. We derive equivalence conditions between early and late fusions within the framework of generalized linear models. Moreover, we analyze the failure conditions of early fusion in the presence of nonlinear feature-label relationships. Furthermore, we propose an approximate equation for evaluating the accuracy of early and late fusion methods as a function of sample size, feature quantity, and modality number. We also propose a critical sample size threshold at which the performance dominance of early fusion and late fusion models undergoes a reversal. Finally, we introduce a fusion method selection paradigm for selecting the most appropriate fusion method prior to task execution and demonstrate its effectiveness through extensive numerical experiments. Our theoretical framework is expected to solve the problems of computational and resource costs in model construction, improving the scalability and efficiency of data fusion methods. Full article

A membrane system was applied for ultrapure water production from the treatment of saline effluent from the canned food industry. The industrial effluent presented a high saline concentration, including sodium chloride, calcium carbonate, calcium sulfates, and magnesium. The effluent was treated using a system of reverse osmosis (RO) and a post-treatment process consisting of ion exchange resins (IEXRs). The RO was accompanied by the addition of a hexametaphosphate dose (2, 6, and 10 mg/L) as an antiscalant to avoid the RO membrane scaling by minerals. In turn, IEXRs were used for water deionization to produce ultrapure water with a reduced concentration of monovalent ions. The antiscalant dose was 6 mg/L, producing clean water from RO permeates with an efficiency of 65–70%. The brine from RO was projected for its reuse in food industry processes. The clean water quality from RO showed 20% total dissolved solids (TDS) removal (equivalent to salts). The antiscalant inhibited the formation of calcium salt incrustation > 200 mg/L, showing low fouling. In turn, anionic resins removed 99.8% of chloride ions, whereas the monovalent salts were removed by a mix of cationic–anionic resin, producing ultrapure water with electrical conductivity < 3.3 µS/cm. The cost of ultrapure water production was 2.62 USD/m³. Full article

In this paper, we investigate the stability of a 1-d wave equation with boundary difference-type delay control. We utilize the idea of system equivalence to find a system with known stability characteristics and select an appropriate regulation mechanism, ensuring that the original system becomes equivalent to the stable one. In this method, we adopt integral-type feedback control, utilizing integral kernel functions as parameters, and determine appropriate parameter functions. The specific steps are as follows: To begin with, an exponentially convergent system is selected as the desired target reference model. Next, we construct a bounded, reversible linear mapping to equate the studied system with the target model. During this process, we derive the expressions for the integral controller and the corresponding kernel function. Subsequently, we prove the solvability of the kernel function. By establishing equations for the kernel function and linear transformations, we find that the initial system exhibits equivalence to the desired model. Ultimately, based on the equivalence between the two systems, we conclude that the original system attains exponential stability under the integral-type feedback controller. Full article

Vascular steal refers to the diversion of blood flow between collateral vessels that share a common inflow restricted by arterial stenosis. Blood is diverted from the high-pressure to the low-pressure, low-resistance system. Vascular steal is associated with anatomical bypass or vasodilation in the collateral network and is called “the arterial steal”. However, we have demonstrated that in the presence of an outflow gradient (e.g., intra-extracranial), blood is shunted to a lower pressure system, a phenomenon we term “venous steal”. Using Thevenin’s equivalent, we generalized the concept of venous steal to apply it to any region of the vascular system with increased outflow pressure. Both arterial steal, caused by increased collateral network conductivity, and venous steal, resulting from lower collateral outflow pressure, reduce compartment perfusion. This occurs indirectly by increasing flow and the pressure gradient across the arterial stenosis, lowering the segmental compartment perfusion pressure—the difference between post-stenotic (inflow) and compartmental (outflow) pressures. Venous steal diverts blood flow from compartments with elevated pressure, such as intracranial, subendocardial, the ischemic core, and regions of focal edema due to inflammation, trauma, or external compression. In shock and low-flow states, it contributes to regional blood flow maldistribution. Treatment of venous steal addresses inflow stenosis, increased compartmental pressure and systemic loading conditions (arterial and venous pressure) to reverse venous steal malperfusion in the ischemic regions. Full article

After a brief review of Carnot’s everlasting contributions to the foundations of thermodynamics, we critically examine the consequences of the Carnot theorem, which leaves behind some lingering questions and confusion that persist even today. What is the one significant aspect of the Carnot cycle that leads to this theorem? When does the working substance play an important role for an engine and what is its correlation with the protocol of operational details? Do all reversible engines working between the same two temperatures have the same maximum efficiency of the Carnot engine as Fermi has suggested? Are all heat engines equivalent to a Carnot engine in disguise? Our new perspective allows for the clarification of these questions with a positive answer for the last question. Recognizing that Carnot eventually abandoned the caloric theory, we use a result by Carnot and simple dimensional analysis to show how the first law, the concept of entropy, and the efficiency of the Carnot engine could have been germinated by Carnot in his time. This then demonstrates that Carnot had good understanding of entropy before its invention by Clausius. We suggest that both should be credited with inventing entropy by calling it Carnot–Clausius entropy. We also clarify some fundamental misconceptions plaguing reversible regenerators and their irreversible replacement by heat exchangers in the field. Full article